Hi > On Oct 22, 2020, at 7:50 AM, Giorgio Barinetti <gior...@barinetti.it> wrote: > > Hi, > > As a newbie in the field, I've collected, by chance, some frequency standards. > > Now is the time to measure them, and see how they perform. > > I've inherited a 5371, but something tells me that is not the right > instrument - and maybe is even faulty. > > So, I'm in the need to buy a counter to use togheter with TimeLab. > > Choices are many, but I'll try to avoid the "older" machines lile 5370 or > 5335. The 531xx series seems nice ( money apart ) > But again : which one between the 3 ? 53131, 53132 or 53181 ?
53181 = single channel 400 ps counter 53131 = dual channel 400 ps counter 53132 = dual channel 100 ps counter 5370 (when working) = dual channel 20 ps counter The gotcha is that none of them are good enough to properly measure 1 second ADEV on a good ( but still could be cheap ) OCXO. A mixer based setup is a cheap way to get things done, even with a 5335. The 531xx counters all share a couple of issues: 1) The power supply was made by who knows who and their quality is not the best. Good news is that the power supply out of a (cheap) 53181 will swap over to revive an expensive 53132. 2) They have a fan, it plugs with dust. When that happens it gets hot inside the cabinet. Things (like the power supply) die as a result. 3) They have a VFD display. It’s a nice one, but they do wear out. Replacing them is problematic. 4) They have a fancy setup to add digits to a frequency measurement. It can lead you astray. It also tends to go deaf right at 10 MHz. There are app notes out there that explain the details. 5) With *any* counter, a good external reference is the way to go for “Time Nut” grade measurements. None of that is to say they are a bad counter, far from it. I have a number of them and have been using them here and at work for decades. The 532xx counters are the latest and greatest. They are on eBay, but not cheap. Bob > > Can somebody shed some light, and maybe help even to found a baseline for us > beginners ? > > Regards, > IZ2JGB > Giorgio > > My NTP servers: (ntpd on FreeBSD - PPS in via Serial) > > HP/Symmetricom 55300A https://www.ntppool.org/scores/93.41.196.243 > > Efratom Rb/Xc GPSDO https://www.ntppool.org/scores/95.255.136.126 > > > > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.